<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      body {
        display: flex;
        justify-content: center; /* 水平居中 */
        align-items: center; /* 垂直居中 */
        height: 100vh; /* 设置 body 高度为视口高度 */
        margin: 0; /* 移除默认的 body 边距 */
      }
    </style>
  </head>
  <body>
    <form action="/shorten" method="post">
      <input type="text" name="url" placeholder="Enter URL" />
      <input type="submit" value="Submit" />
    </form>
  </body>
</html>
